In general, the invention relates to an apparatus and method for making fabricated snack food products such as potato crisps or tortilla chips. More particularly, the invention relates to an apparatus and method for form-frying such products.
In general, snack food chips which are made from potato, corn, or other farinaceous dough and which are formed or fabricated such that the chips all have the same shape and/or configuration are known in the art. Packaging fabricated snack food chips in a stacked arrangement in cylindrical canisters is also known in the art and has been found to be popular for a number of reasons. Such canisters provide some degree of protection against breakage of the snack food chips, and they provide greater transportability of the snack food product, both in terms of bulk transport (i.e., large cartons of the canisters being shipped, e.g., from the manufacturer to the retailer) and in terms of the individual consumer being able to transport a single package of chips (e.g., in a purse or in a picnic basket). Additionally, the extended shelf life of a sealed canister of snack food chips as compared to a bag (commonly pillow-shaped and sometimes filled with a generally inert gas to prevent product degradation), as well as the ability to seal a canister with a snap-fit-type lid once the canister has been opened, makes a canister a particularly attractive packaging option.
In order to manufacture and package form-fried snack food chips efficiently, it is necessary to maintain control over the product configuration and arrangement throughout the fabrication process. In the past, this requirement has been met by using enclosed molds to shape or form the snack chips and to restrain them as they are transported through a cooking medium such as hot oil. However, not only is such an apparatus complex and therefore relatively prone to mechanical failure, but the complexity limits how close together the chips can be arranged in the production line and therefore limits the productivity of the apparatus. Additionally, the volume of oil or other cooking medium used with such apparatus also tends to be relatively large. Accordingly, the cost of operating the system is generally higher than would be desired.
The invention provides an apparatus and method for making fabricated snack food chips which are uniformly shaped and configured. The apparatus is compact and elegantly simple in design and overcomes the above-noted shortcomings extant in the prior art apparatus and methodologies.
In particular, the invention features a drum-type frying apparatus which transports snack food chip preforms through a relatively small volume of hot oil that is contained within a space formed between the drum and the surrounding wall of a housing in which the drum is supported. The drum has perforated mold elements disposed around its periphery, and the chip preforms are supported on the mold elements by drawing suction through the perforations.
A series of vacuum rollers transfer the uncooked chip preforms from a cutter roller assembly onto the mold elements using perforated pick-up and transfer members arranged around the perimeters of the vacuum rollers. Similarly, a take-off roller uses perforated pick-up and transfer members disposed around its perimeter to remove the cooked chips from the fryer drum. The cooked snack food chips are then removed from the take-off roller and transported downstream for subsequent processing (e.g., light re-oiling and seasoning) and packaging (e.g., in canisters, which may preferably conform to the contour or perimeter of the cooked chips).
The inventive apparatus and method allow one to produce form-fried snack food chips which are uniform in shape and configuration quickly and conveniently and with enhanced process control. Additionally, the amount of oil used in the process is minimized. Because relatively less oil is present in the apparatus at any given time as compared to prior art apparatus, the oil is used and replenished or xe2x80x9cturned overxe2x80x9d more frequently, and therefore the oil quality remains high.
Furthermore, and quite significantly, the configuration of the apparatus minimizes exposure of the oil to the ambient atmosphere. This is because whereas the two-piece prior art enclosed mold cavities presented multiple surfaces over which the oil could spread in the form of a film, thus creating a large oil surface area which could oxidize when exposed to the ambient air, the present invention utilizes just a single mold surface to shape the snack food product, thereby minimizing the amount of oil (in the form of an oil film spread over the metal surfaces) that is exposed to the atmosphere and that is susceptible to degrading oxidation. Additionally, the apparatus of the invention preferably includes means for controlling the nature of the atmosphere to which the oil is exposed. In particular, the portion of the apparatus where the snack food chips enter the fryer and are removed from the fryer preferably is shrouded, and an gas such as carbon dioxide or nitrogen is injected into the shrouded area to minimize exposure of the oil to oxygen. These features of the invention significantly improve the quality of the snack food chips produced by the system.